Chemistry Commons^™

Textured Nise₂ Film: Bifunctional Electrocatalyst For Full Water Splitting At Remarkably Low Overpotential With High Energy Efficiency, Abdurazag T. Swesi, Jahangir Masud, Wipula P. R. Liyanage, Siddesh Umapathi, Eric W. Bohannan, Julia E. Medvedeva, Manashi Nath

Physics Faculty Research & Creative Works

Herein we have shown that electrodeposited NiSe₂ can be used as a bifunctional electrocatalyst under alkaline conditions to split water at very low potential by catalyzing both oxygen evolution and hydrogen evolution reactions at anode and cathode, respectively, achieving a very high electrolysis energy efficiency exceeding 80% at considerably high current densities (100 mA cm^-2). The OER catalytic activity as well as electrolysis energy efficiency surpasses any previously reported OER electrocatalyst in alkaline medium and energy efficiency of an electrolyzer using state-of-the-art Pt and RuO₂ as the HER and OER catalyst, respectively. Through detailed electrochemical and …

Mechanisms Of Euv Exposure : Photons, Electrons And Holes, Amrit Kausik Narasimhan

Legacy Theses & Dissertations (2009 - 2024)

The microelectronics industry’s movement toward smaller and smaller feature sizes has necessitated a shift to Extreme Ultra-Violet (EUV) lithography to be able to pattern sub 20-nm features, much like earlier shifts from i-line to 248 nm. However, this shift from 193-nm lithography to EUV (13.5 nm) poses significant obstacles. EUV is the first optical lithography to operate in an energy range (92 eV per photon vs. 6.4 eV per photon for 193 nm lithography) above the electron binding energies of common resist atomic species. This significant energy increase complicates resist design. For exposures of equal dose, resists receive 14 times …

Design And Activation Of Frequency Tunable 200ghz Gyrotron, Natalie Golota, Faith Scott, Edward Saliba, Brice Albert, Alexander Barnes

Undergraduate Research Symposium Posters

Dynamic Nuclear Polarization (DNP) when combined with Nuclear Magnetic Resonance (NMR) yields high sensitivity spectra while decreasing sample acquisition time. DNP transfers polarization from electron to nuclear spins, giving a strong enhancement of NMR signal. DNP is rapidly developing area of research due in part to application of cyclotron resonance masers (gyrotron) as high power microwave sources. Gyrotrons provide a high-power, high-frequency microwave source that can be used in close proximity to high field NMR magnets. Gyrotrons are operated under strong vacuum and within a cryogenic superconducting magnetic. Gyrotron microwave power is generated by a magnetron injection gun (MIG) composed …

Using Low-Coherence Interferometry To Monitor Cell Invasion In An In-Vitro Model System, Behnaz Davoudi Nasab

Honors Undergraduate Theses

In an optically random system, such as naturally occurring and man-made media, light undergoes pronounced multiple scattering. This phenomenon has shown a remarkable potential in characterizing complex materials. In this regime, scattering occurs from each individual center of the scattering and independent scattering events lead to multiple light scattering. This phenomenon is often described as a random walk of photons and can be modeled in terms of a diffusion equation based on the radiative transfer theory. In this thesis, we used optical path-length spectroscopy (OPS), which is an experimental method to obtain the path-length probability density of the propagating light …

Micro-Spectroscopy Of Bio-Assemblies At The Single Cell Level, Jeslin Kera

Honors Undergraduate Theses

In this thesis, we investigate biological molecules on a micron scale in the ultraviolet spectral region through the non-destructive confocal absorption microscopy. The setup involves a combination of confocal microscope with a UV light excitation beam to measure the optical absorption spectra with spatial resolution of 1.4 μm in the lateral and 3.6 μm in the axial direction. Confocal absorption microscopy has the benefits of requiring no labels and only low light intensity for excitation while providing a strong signal from the contrast generated by the attenuation of propagating light due to absorption. This enables spatially resolved measurements of single …

New And Improved Infra-Red Absorption Cross Sections And Ace-Fts Retrievals Of Carbon Tetrachloride (Ccl4), Jeremy J. Harrison, Christopher D. Boone, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Carbon tetrachloride (CCl₄) is one of the species regulated by the Montreal Protocol on account of its ability to deplete stratospheric ozone. As such, the inconsistency between observations of its abundance and estimated sources and sinks is an important problem requiring urgent attention (Carpenter et al., 2014) [5]. Satellite remote-sensing has a role to play, particularly limb sounders which can provide vertical profiles into the stratosphere and therefore validate stratospheric loss rates in atmospheric models. This work is in two parts. The first describes new and improved high-resolution infra-red absorption cross sections of carbon tetrachloride/dry synthetic air over …

The Hitran2016 Molecular Spectroscopic Database, I. E. Gordon, L. S. Rothman, C. Hill, R. V. Kochanov, Y. Tan, P. F. Bernath, M. Birk, V. Boudon, A. Campargue, K. V. Chance

Chemistry & Biochemistry Faculty Publications

This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional …

Methods For Producing Graphene From Petroleum By-Products, Eva M. Deemer

Open Access Theses & Dissertations

N/A

Manifestations Of Classical Physics In The Quantum Evolution Of Correlated Spin States In Pulsed Nmr Experiments, Martin K. Ligare

Faculty Journal Articles

Multiple-pulse NMR experiments are a powerful tool for the investigation of mole- cules with coupled nuclear spins. The product operator formalism provides a way to understand the quantum evolution of an ensemble of weakly coupled spins in such experiments using some of the more intuitive concepts of classical physics and semi- classical vector representations. In this paper I present a new way in which to inter- pret the quantum evolution of an ensemble of spins. I recast the quantum problem in terms of mixtures of pure states of two spins whose expectation values evolve identi- cally to those of classical …

Investigations Into Structure And Properties Of Atomically-Precise Transition Metal-Chalcogenide Clusters Of Crte And Ligated Cr6te8(Pet3)6, Anthony F. Pedicini

Theses and Dissertations

The complete understanding of a clusters electronic structure, the primary mechanisms for its properties and stabilization is necessary in order to functionalize them for use as building blocks within novel materials. First principle theoretical studies have been carried out upon the electronic properties of Cr_xTe_y (x = 1 – 6, y = 0 – 8, x + y ≤ 14), as well as for the larger triethylphosphine (PEt₃) ligated cluster system of Cr₆Te₈(PEt₃)₆. Together, we aim to use the information garnered from the smaller clusters to address …

Thermal Conductivities Of Organic Semiconductors, Yulong Yao

Theses and Dissertations--Physics and Astronomy

Organic semiconductors have gained a lot of interest due to their ease of processing, low-cost and inherent mechanical flexibility. Although most of the research has been on their electronic and optical properties, knowledge of the thermal properties is important in the design of electronic devices as well. Our group has used ac-calorimetric techniques to measure both in-plane and transverse thermal conductivities of a variety of organic semiconductors including small-molecule crystals and polymer blends. For layered crystals composed of molecules with planar backbones and silylethynyl (or germylethynyl) sidegroups projecting between the layers, very high interplanar thermal conductivities have been observed, presumably …

Improving Nuclear Safety, Security, And Nonproliferation In Northeast Asia Through Multinational Approach, Viet Phuong Nguyen

International Journal of Nuclear Security

No abstract provided.

Nuclear Power: Black Sky Liability Or Black Sky Asset?, Sherrell R. Greene

International Journal of Nuclear Security

Ready access to abundant electricity is a key enabler of modern life. During the past decade the vulnerability of Critical Infrastructure sectors in the U.S. to a variety of natural hazards and man-made threats has become increasingly apparent. The electrical infrastructure (the “Grid”) is the foundation for all other critical civil infrastructures upon which our society depends. Therefore, protection of the Grid is an energy security, homeland security, and national security issue of highest importance. Geomagnetic disturbances (GMD) induced by solar coronal mass ejections (CMEs), electromagnetic pulse (EMP) attacks, and cyber attacks are three events having the potential to plunge …

Addressing The Tunnel Threat At Nuclear Facilities: A Case Study, Md. Mobasher Ahmed

International Journal of Nuclear Security

No abstract provided.

Janus Realized: The Use Of Social Media As A Means Of Transparency Nuclear Communication To The Public, Frances Bachstein

International Journal of Nuclear Security

No abstract provided.

Letter From The Editor

International Journal of Nuclear Security

No abstract provided.

Table Of Contents

International Journal of Nuclear Security

No abstract provided.

Modern Advancements In Post-Detonation Nuclear Forensic Analysis, S. Adam Stratz, Jonathan A. Gill, John D. Auxier Ii, Howard L. Hall

International Journal of Nuclear Security

Deterring nuclear terrorism is a critical national asset to support the preclusion of non-state actors from initiating a nuclear attack on the United States. Successful attribution of a detonated nuclear weapon allows for timely responsive measures that prove essential in the period following a nuclear event. In conjunction with intelligence and law enforcement evidence, the technical nuclear forensics (TNF) post-detonation community supports this mission through the development and advancement of expertise to characterize weapon debris through a rapid, accurate, and detailed approach. Though the TNF field is young, numerous strides have been made in recent years toward a more robust …

Evaluation Of Covert Plutonium Production From Unconventional Uranium Sources, Ondrej Chvala, Steven Skutnik, Tyrone Christopher Harris, Emily Anne Frame

International Journal of Nuclear Security

The potential for a relatively non-advanced nation to covertly acquire a significant quantity of weapons-grade plutonium using a gas-cooled, natural uranium-fueled reactor based on relatively primitive early published designed is evaluated in this article. The economic and technical issues that would influence the design decisions of a covert ²³⁹Pu production program are considered.

Several unconventional uranium acquisition approaches were explored. Methods for extracting uranium from enrichment tails, seawater, and coal ash sources were considered. The evaluation indicated that uranium extraction from coal ash or insitu leaching from underground deposits could be performed in economical manner that might be difficult …

Student Competition Cover

International Journal of Nuclear Security

No abstract provided.

Prospects For Cooperation On Tackling Nuclear And Radiological Terrorism In South Asia: India–Pakistan Nuclear Detection Architecture, Muhammad Umer Khan

International Journal of Nuclear Security

No abstract provided.

Table Of Contents

International Journal of Nuclear Security

No abstract provided.

From The Editor’S Desk

International Journal of Nuclear Security

No abstract provided.

Opportunities And Challenges In Developing Nuclear Security In Africa, James Larkin Mfr

International Journal of Nuclear Security

Those involved in nuclear security recognize that regions of significant instability in Africa have an impact on the safety and security of the continent's nuclear material and un-enriched uranium; however, some countries outside of continental Africa have taken counterproductive approaches to this issue. Despite challenges, the nuclear security community continues to develop and apply appropriate levels of nuclear security where needed. The community also takes every opportunity to make significant contributions to the global discourse on nuclear security culture.

Legal And Regulatory Framework Of Nuclear Security In Indonesia, Dahlia Cakrawati Sinaga

International Journal of Nuclear Security

Nuclear security is one of the most important topics for regulatory purposes in Indonesia. Nuclear security measures exist to prevent, detect, and respond to unauthorized removal of radioactive material and the sabotage of nuclear and radiation facilities. Indonesia participates in bilateral and multilateral cooperation and international events such as the Nuclear Security Summit. Indonesia has also ratified several international instruments related to nuclear security. Based on commitment to international events and ratification, Indonesia has developed nuclear security infrastructures by strengthening legislation and regulation, enhancing building capacity, and strengthening equipment and facilities. Badan Pengawas Tenaga Nuklir (BAPETEN) is Indonesia’s nuclear energy …

Nuclear Security Risk Analysis: An Insider-Outsider Collusion Scenario, Mohammad A. Hawila, Sunil S. Chirayath

International Journal of Nuclear Security

This study analyses the vulnerability of the physical protection system (PPS) deployed at a hypothetical facility. The PPS is designed to prevent and eliminate threats to nuclear materials and facilities. The analysis considers possible outsider and insider threats. A modified adversary sequence diagram (ASD) evaluates threat pathways to test an insider-outsider collusion case. The ASD also measures the probability of adversary interruption by demonstrating the methodology for a typical nuclear facility.

Nuclear Security Culture And Batan’S Assessment: Batan’S Experience, Anhar R. Antariksawan

International Journal of Nuclear Security

Organizations should increase safety to minimize the harmful effects of nuclear materials. Additionally, organizations should take measures to protect security culture within the organization itself. This paper covers the National Nuclear Energy Agency of Indonesia’s (BATAN’s) promotion of nuclear security culture and self- assessment projects, which is based on the International Atomic Energy Agency’s (IAEA) methodology.

Modified Fault Tree Method For Vulnerability Analysis Of Nuclear Medicine Facility Security System Case Study: Radiotherapy Facility, Sardjito General Hospital, Haryono Budi Santosa

International Journal of Nuclear Security

Assessing the vulnerability of physical protection systems (PPS) in nuclear medicine facilities is needed to prevent a security incident that could lead to the malicious use of nuclear material. Theft and sabotage of nuclear materials is becoming globally recognized. The current methods of assessing vulnerability tend to be oriented toward complex nuclear security; consequently, it is excessive to use such methods in simple facilities (i.e., radiotherapy facilities in hospitals).

The fault tree analysis is a method to assess vulnerability for a simple nuclear facility. The method’s primary events (i.e., basic events and undeveloped events) are able to accommodate fault causes …

Ua66 Ogden College Of Science & Engineering Newsletter, Wku Ogden College Of Science & Engineering

Ogden College of Science & Engineering Publications

Newsletter created by and about WKU Ogden College of Science & Engineering.

• Ogden College Hall Taking Shape on TIme & on Budget
• Alumni Focus: Dr. Talia McKinney Collins
• WKU Research Foundation Launches New Website
• French, Jackson. Stemshot Rocketry Competition
• Agriculture
• Architectural & Manufacturing Sciences
• Grants & Publications
• Dr. Noah Ashley Receives NIH Grant
• Biology - News & Notes
• WKU Chemistry Welcomes Dr. Lawrence Hill & Dr. David Wolfgang
• Gary Kwong Receives McNally Award
• Student Teams Compete in National Engineering Contests Over the Summer
• Geology Major Conducts Research in Ethiopia - Deborah Flynn
• Geography & Geology
• WKU Meterology Launches White Squirrel …

Ijns Masthead

International Journal of Nuclear Security

No abstract provided.